<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
	</head>
	<body>
		<script>
		// var s1 = new Set([1,2,1,2,5,9,9,8]);
		// console.log(s1);
		
		// set常用来去重		
		// var arr = [1,2,1,2,1,1,2];
		// var arr1 = [...new Set(arr)];
		// console.log(arr1)
		
		var s1 = new Set([1,2,1,2,5,9,9,8]);
		// add添加 delete删除 clear清空 has检测 size大小
		console.log(s1.size);
		s1.add(88);
		s1.delete(9);
		console.log(s1);
		
		
		</script>
	</body>
</html>
